package leetcode.editor.cn;

public class Solution236 {
    public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
        if (root == null) return null;
        if (root == p && root == q) return root;
        TreeNode left = lowestCommonAncestor(root.left, p, q);
        TreeNode right = lowestCommonAncestor(root.right, p, q);
        if (left!=null && right!=null){
            return root;
        }
        if (left==null && right==null){
            return null;
        }
        return left==null?right:left;
    }
}
